body{margin:0;font-size:28px;font-family:Arial, Helvetica, sans-serif;}.header{background-color:#f1f1f1;padding:30px;text-align:center;}#navbar{overflow:hidden;background-color:#333;}#navbar a{float:left;display:block;color:#f2f2f2;text-align:center;padding:14px 16px;text-decoration:none;font-size:17px;}#navbar a:hover{background-color:#ddd;color:black;}#navbar a.active{background-color:#4CAF50;color:white;}.content{padding:16px;}.sticky{position:fixed;top:0;width:100%;}.sticky + .content{padding-top:60px;}